List of words that may be spelled with a ligature
This list of words that may be spelled with a ligature in English encompasses words which have letters that may, in modern usage, either be rendered as two distinct letters or as a single, combined letter. This includes AE being rendered as Æ and OE being rendered as Œ.
Until the early twentieth century, the œ and æ ligatures had been commonly used to indicate an etymological connection with Latin or Greek. Since then they have fallen out of fashion almost completely and are now only used occasionally. They are more commonly used for the names of historical people, to evoke archaism, or in literal quotations of historical sources. These ligatures are proper letters in some Scandinavian languages, and so are used to render names from those languages, and likewise names from Old English. Some American spellings replace ligatured vowels with a single letter; for example, gynæcology or gynaecology is spelled gynecology.
The fl and fi ligatures, among others, are still commonly used to render modern text in fine typography. Page-layout programs such as QuarkXPress and Adobe InDesign can be configured to automatically replace the individual characters with the appropriate ligatures. However this is a typographic feature and not part of the spelling.
[Æ]
Note that some words contain an ae which may not be written æ because the etymology is not from the Greek -αι- or Latin -ae- diphthongs. These include:- In instances of aer when it makes the sound IPA . Comes from the Latin āër, Greek ἀήρ.
- When ae makes the diphthong or .
- When ae is found in a foreign phrase or loan word and it is unacceptable to use the ligature in that language. For example, when in a German loan word or phrase, if the a with an umlaut is written as ae, it is incorrect to write it with the ligature.
| Non-ligature form | Ligature form | Other forms | Etymology |
| ' | acanthæsthesia | acanthesthesia | From Ancient Greek + |
| Achaean | Achæan | Achean, Achaian, Akhaian | From Latin or, from Ancient Greek |
| Aeaea | Ææa | Eëä | From Greek Αἰαία |
| ' | æciospore | aeciospore | New Latin aecium from Ancient Greek and New Latin spora from Ancient Greek |
| ' | æcidium | New Latin aecidium, from Greek αἰκία | |
| ' | æcium | New Latin aecidium, from Greek αἰκία | |
| aedicule | ædicule | edicule | From Latin , diminutive of |
| Aegis | Ægis | Egis | Latin from Greek Αἰγίς |
| Aegyptus | Ægyptus | Egyptus | Latin from Greek Αἴγυπτος |
| Aelfred | Ælfred | Alfred | Old English—see Alfred |
| Aenon | Ænon | From Greek, Αἰνών | |
| ' | Æolian | Eolian | Latin Aeolis from Greek mythology Αἰολίς ' |
| Aeolis | Æolis | — | Latin Aeolis, from Greek Αἰολίς |
| aeon | æon | eon | Late Latin aeon, from Greek αἰών. |
| ' | æra | era | |
| aerugite | ærugite | Latin aerugo, from aes | |
| aerugo | ærugo | Latin aerugo, from aes | |
| aeschynite | æschynite | eschynite | Greek αἰσχύνω |
| aesculin | æsculin | esculin | |
| aesculetin | æsculetin | esculetin | |
| Aesop | Æsop | Esop | Ancient Greek Αἴσωπος |
| aesthetic | æsthetic | esthetic | Greek αἰσθετικός |
| ' | æstival | estival | Latin aestivus, from aestas |
| ' | æstivation | estivation | Latin aestivare, from aestivus, from aestas |
| ' | Æther | ether | Latin aether, from Greek αἰθήρ |
| ' | æthereal or ætherial | ethereal, ethereal, aetherial | |
| Aethelthryth | Æthelthryth | Audrey | Anglo-Saxon |
| Aethrioscope | Æthrioscope | Ethrioscope | Greek αἴθριον |
| aetiology | ætiology | etiology | |
| algae | algæ | algas | |
| Alphaeus | Alphæus | ||
| ' | ' | — | From Latin ' + ' ), a calque of Ancient Greek . |
| anaemia | anæmia | anemia | |
| anaesthesia | anæsthesia | anesthesia | |
| anapaest | anapæst | anapest | |
| ' | antennæ | antennas | |
| archaeology | archæology | archeology | |
| archaebacteria | archæbacteria | archaea/archæ | |
| ' | Athenæum | Atheneum | |
| ' | azotæmia | azotemia | |
| bacteraemia | bacteræmia | bacteremia | |
| Caedmon | Cædmon | Cadmon | |
| ' | Cæsar | Cesar | |
| caesium | cæsium | cesium | |
| Chaldaea | Chaldæa | Chaldea | |
| chaetophorous | chætophorous | chetophorous | |
| chimaera | chimæra | chimera | |
| coaeval | coæval | coeval | |
| curriculum vitae | curriculum vitæ | — | Latin meaning ‘course of life’, vitæ |
| cyclopaedia | cyclopædia | cyclopedia | |
| daedal | dædal | dedal | |
| ' | dæmon | demon | Greek: δαιμων |
| ' | diæresis | dieresis | |
| Egypt | Ægypt | Aegypt | From the Latinised Ægyptus |
| encyclopaedia | encyclopædia | encyclopedia | |
| ' | ænigma | aenigma | |
| Epaenetus | Epænetus | — | |
| era | æra | aera | Late Latin aera, probably from Latin æs |
| et cetera | et cætera | et caetera, etc., &c. | Latin phrase |
| ' | æternal | aeternal | |
| Ethiopia | Æthiopia | Aethiopia | |
| Eudaemonic | eudæmonic | eudemonic | |
| faeces | fæces | feces | |
| fairy | færie | faerie | |
| formulae | formulæ | formulas | |
| fraenum | frænum | Frenum | |
| Gaea | Gæa | Gaia | |
| Graeco-Roman | Græco-Roman | Greco-Roman | |
| haemoglobin | hæmoglobin | hemoglobin | |
| haemolysis | hæmolysis | hemolysis | |
| haemophilia | hæmophilia | hemophilia | |
| haemorrhage | hæmorrhage | hemorrhage | |
| haemorrhoid | hæmorrhoid | hemorrhoid | |
| hyaena | hyæna | hyena | |
| Hymenaeus | Hymenæus | — | |
| hypaethral | hypæthral | hypethral | |
| hyperbolae | hyperbolæ | hyperbolas | |
| hypnopedia | hypnopædia | — | |
| Idumaea | Idumæa | Idumea | From "Edom". |
| Irenaeus | Irenæus | — | |
| ischaemia | ischæmia | ischemia | |
| Ituraea | Ituræa | Iturea | |
| ' | Judæo- | Judeo- | |
| ' | judæophobe | judeophobe | |
| leukaemia | leukæmia | leukemia | |
| medieval | mediæval | mediaeval | |
| nebulae | nebulæ | nebulas | plural – New Latin → Latin ; akin to Old High German nebul → Greek nephelē, nephos |
| nymphae | nymphæ | nymphs | |
| nymphaea | nymphæa | — | |
| orthopaedic | orthopædic | orthopedic | |
| paean | pæan | pean | |
| ' | pæon | — | |
| pedagogue | pædagogue or pædagog | pedagog , | |
| pederasty | pæderasty | paederasty | |
| paediatrics | pædiatrics | pediatrics | |
| paediatrician | pædiatrician | pediatrician | |
| paediatrist | pædiatrist | pediatrist | |
| paedophile | pædophile | pedophile | |
| palaeobotany | palæobotany | paleobotany | |
| palaeocene | palæocene | paleocene | |
| palaeoclimatology | palæoclimatology | paleoclimatology | |
| palaeography | palæography | palaeography | |
| palaeolithic | palæolithic | paleolithic | |
| palaeography | palæography | paleography | |
| palaeontology | palæontology | paleontology | |
| palaeozoic | palæozoic | paleozoic | |
| Panacaea | Panacæa | Panacea | |
| ' | pandæmonium | pandaemonium | |
| Pangaea | Pangæa | Pangea | |
| parabolae | parabolæ | parabolas | |
| personae | personæ | personas | |
| Plantae | Plantæ | ||
| ' | præmium | praemium | |
| pretorium | prætorium | praetorium, also prœtorium | Both forms with æ and œ seen, from Latin, praetōrium |
| Primeval | primæval | primaeval | |
| Quaestor | Quæstor | — | |
| Rhaetia | Rhætia | — | |
| septicaemia | septicæmia | septicemia | |
| scarabaeid | scarabæid | — | |
| scarabaeoid | scarabæoid | — | |
| subpoenae | subpœnæ | — | |
| supernovae | supernovæ | supernovas | |
| synaeresis | synæresis | syneresis | |
| synaesthesia | synæsthesia | synesthesia | |
| Thaddaeus | Thaddæus | Thaddeus | |
| toxaemia | toxæmia | toxemia | |
| uraemia | uræmia | uremia | |
| vertebrae | vertebræ | ||
| ' | viræmia | viremia | |
| Zacchaeus | Zacchæus | Zaccheus | |
| zoöglœæ' |